diff --git a/src/H5B.c b/src/H5B.c
index 1531ded23a..a8b8eebe80 100644
--- a/src/H5B.c
+++ b/src/H5B.c
@@ -2054,7 +2054,7 @@ H5B_copy(H5F_t *f, const H5B_t *old_bt)
     H5B_t		*ret_value = NULL;
     hsize_t		total_native_keysize;
     hsize_t		size;
-    hsize_t     nkeys;
+    intn                nkeys;
     uintn		u;
 
     FUNC_ENTER(H5B_copy, NULL);